Strongly typed ConfigurationManager in .NET Framework

Handling configuration files in .NET Framework is often tedious. You retrieve the app setting as a string and must then parse it out. Dont you wish we could have a generic method to get a strongly typed app setting instead and spare ourselves with some code ? Sure you can!

using System;
using System.ComponentModel;
using System.Configuration;

namespace Hemit.OpPlan.Common.Extensions
{

    /// <summary>
    /// Utility methods for ConfigurationManager. Also included methods for handling OpenExeConfiguration (running process configuration, for example in tests and installers)
    /// </summary>
    public static class ConfigurationManagerWrapper
    {
        /// <summary>
        /// Sets an appsetting for the exe configuration
        /// </summary>
        /// <param name="appsetting"></param>
        /// <param name="value"></param>
        public static void SetAppsettingForExecConfiguration(string appsetting, object value)
        {
            System.Configuration.Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
            config.AppSettings.Settings[appsetting].Value = Convert.ToString(value);
            config.Save(ConfigurationSaveMode.Modified);
        }

        /// <summary>
        /// Sets an appsetting for the exe configuration
        /// </summary>
        /// <param name="appsetting"></param>
        /// <param name="value"></param>
        public static string GetAppsettingExecConfiguration(string appsetting, object value)
        {
            return ConfigurationManager.AppSettings[appsetting];
        }

        /// <summary>
        /// Sets an appsetting for the exe configuration
        /// </summary>
        /// <param name="appsetting"></param>
        /// <param name="value"></param>
        public static void SetAppsettingForConfiguration(string appsetting, object value)
        {
            ConfigurationManager.AppSettings[appsetting] = Convert.ToString(value);
        }

        /// <summary>
        /// Sets an appsetting for the exe configuration
        /// </summary>
        /// <param name="appsetting"></param>
        /// <param name="value"></param>
        public static string GetAppsettingForExecConfiguration(string appsetting, object value)
        {
            System.Configuration.Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
            return config.AppSettings.Settings[appsetting].Value;
        }


        /// <summary>
        /// Use this extension method to get a strongly typed app setting from the configuration file.
        /// Returns app setting in configuration file if key found and tries to convert the value to a specified type. In case this fails, the fallback value
        /// or if NOT specified - default value - of the app setting is returned
        /// </summary>
        /// <typeparam name="T"></typeparam>
        /// <param name="appsettingKey"></param>
        /// <param name="fallback"></param>
        /// <returns></returns>
        public static T GetAppsetting<T>(string appsettingKey, T fallback = default(T))
        {
            string val = ConfigurationManager.AppSettings[appsettingKey] ?? "";
            if (!string.IsNullOrEmpty(val))
            {
                try
                {
                    Type typeDefault = typeof(T);
                    var converter = TypeDescriptor.GetConverter(typeof(T));
                    return converter.CanConvertFrom(typeof(string)) ? (T)converter.ConvertFrom(val) : fallback;
                }
                catch (Exception err)
                {
                    Console.WriteLine(err); //Swallow exception
                    return fallback;
                }
            }
            return fallback;
        }

    }
}

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